The aim of this project is to develop a portable, low cost, fast and easy-to-use device for the quantitative assessment of bone quality that is suitable for mass screening and early identification of those at risk for osteoporosis. The device will detect changes in the composition and micro-architectural properties of bone by measuring the ultrasound velocity, attenuation, spectral, and non-linear acoustic (NLA) parameters of bone at multiple sites along the skeleton with varied proportion of spongy and compact bone components. The manual scanning probe operating in surface pulse transmission mode will be used to obtain ultrasonic profiles in tested skeletal area. The diagnostic potential of NLA spectroscopy as a novel method for detecting the accumulation of microdamage in living bone will be evaluated. The feasibility of the proposed methods and devices has been proven in laboratory model studies and in pilot clinical trials. In Phase II of the project designed during Phase I will be developed into a fully functional and compact bone ultrasonometer with the manual scanning and NLA modes of operation, and clinically tested. Indexes of bone quality composed of several ultrasonic parameters will be developed for differential diagnostics of osteoporosis and mixed osteopenia. PROPOSED COMMERCIAL APPLICATIONS: Early evaluation and monitoring of osteoporosis is imperative for timely and effective treatment of the disease. According to the National Osteoporosis Foundation [1998 Report] the current economic burden associated with osteoporosis-related fractures is estimated at about $13.8 billion annually. There is an urgent need for advancement of the existing diagnostic techniques. The Proposed multi-site ultrasonometer offers higher diagnostic efficacy and specificity, lower cost, portability, and ease of operation. Developed device is ideally suited for the mass screening of osteoporosis and primary monitoring of population with high fracture risk.